Target throwing arm with target detent mechanism

ABSTRACT

An eccentrically disposed target on a rotating platform is released by a mechanism which includes a detent carried by the platform and engaging a forward edge of the target whereby the target is restrained from moving along the surface of the platform under the influence of the centrifugal forces exerted on the target by the rotation of the platform. In order to release the target the detent, which is mounted on a rotatable shaft, is moved out of the path of motion of the target by rotation of the shaft at such a speed that the portion of the detent which had engaged the target moves away from the target with a horizontal component of velocity, along the path of travel of the target, greater then the velocity at which the target moves along the surface of the platform under the influence of the centrifugal forces. A bent shaft with a resilient sleeve on the free end that engages a target may be used as a detent.

United States Patent 11 1 Darrell TARGET THROWING ARM WITH TARGET DETENTMECHANISM [76] Inventor: George H. Darrell, 25 Chestnut,

Dedham, Mass. 02026 [22] Filed: Mar. 22, 1973 [21] Appl. No.: 343,636

Italy 124 6 Primary Exqminer--Richard C. Pinkham AssistantExaminerWilliam R. Browne Attorney, Agent, or FirmElmer J. Gorn [57]ABSTRACT An eccentrically disposed target on a rotating platform isreleased by a mechanism which includes a de tent carried by the platformand engaging a forward edge of the target whereby the target isrestrained from moving along the surface of the platform under theinfluence of the centrifugal forces exerted on the target by therotation of the platform. In order to release the target the detent,which is mounted on a rotatable shaft, is moved out of the path ofmotion of the target by rotation of the shaft at such a speed that theportion of the detent which had engaged the target moves away from thetarget with a horizontal component of velocity, along the path of travelof the target, greater then the velocity at which the target moves alongthe surface of the platform under the influence of the centrifugalforces. A bent shaft with a resilient sleeve on the free end thatengages a target may be used as a detent.

7 9 5991, Drawin .F FEEL? was TARGET THROWING ARM WITH TARGET DETENTMECHANISM BACKGROUND OF THE INVENTION This invention relates to targetthrowing traps and, more particularly, to a release mechanism for thetarget that is eccentrically disposed on a rotating platform prior torelease.

In one type of known target throwing trap, a target is disposedeccentrically onto the surface of a rotating platform and is held inthis position by a release mechanism until the target is released. Whenthe target is released, the forces acting on the target throw the targetaway from the platform.

Target throwing traps are more effective when the line of flight of thetarget upon release is predictable. Also, while the targets are made ofa fragile material, the trap should not break the targets at release.

A target throwing trap is disclosed in U.S. Pat. No. 3,108,582 to thesame inventor as in the present invention. The targets are located abovea box-shaped, rotating platform. A disc lowers one of the targets ontothe rotating platformso that the target is concentrically disposedthereon. A device then pushes the target a distance across the rotatingplatform whereby the target becomes eccentrically disposed on therotating platform. A release mechanism and an arrangement of guiderailsprevent further motion of the target across the surface of the platformuntil the target is released.

When the release mechanism is activated, the target is no longerrestrained, and the centrifugal forces cause the target to pass throughthe guiderails and to undergo flight. A vertical shaft is rotatablymounted through the upper and lower surfaces of the rotating platfonn.When a cam mechanism which is associated with the lower, end of thisshaft is activated, the shaft rotates through an arc. The vertical shaftthen rotates a crank arm that imparts longitudinal motion to a triggerblock. The block which originally contacted the target moves away fromthe target in a direction generally transverse to the flight path of thetarget.

' While the release mechanism disclosed in U.S. Pat.

No. 3,108,582 has been generally successful, it was disfor translating arotation of the vertical shaft to a rotation of the horizontal shaft.Preferably, the gear assembly has a 2 to 1 transmission ratio to permitthe release member to rotate 90 for a 45- rotation of the verticalshaft. Also, it is preferably to pad the release detent with a resilientmaterial to cushion the contact between the release detent and thetarget. The release detent may be a tab affixed to the end of thehorizontal shaft or the horizontal shaft may be formed with a bend sothat the end portion of the shaft may form the release detent.

The primary advantage of the present invention resides in moving therelease detent parallel to the flight path as opposed to the transversemovement of the trigger block in U.S. Pat. No. 3,108,582. When therelease detent such as the trigger block, moves transversely,

the release detent and the target are in contact for the 7 duration ofmovement of the detent. Thus, friction is covered that the flight pathof the target varied within SUMMARY OF THE INVENTION There is providedin accordance with the present increated which results in accuracyerrors and target breakage. When the release detent moves parallel tothe flight path, friction is reduced because once the release detentstarts to rotate, the target no longer contacts the release detent.

Another feature of the invention includes an arrangement for adjustingthe location of the release detent to establish an optimum initialtarget location.

BRIEF DESCRIPTION OF THE-DRAWINGS FIG. 1 is a plan view of the rotatingplatform showing its relation to the target and the release mechanism;

FIG. 2 is an elevational view in partial section of the improved releasemechanism according to the present invention; i v

FIG. 3 is a plan view of the release mechanism at the time of releasewith portions of the mechanism removed;

FIG. 4 is a plan view of a modified form of release mechanism.

-DESCRIPT ION OF PREFERRED EMBODIMENTS The invention is herein shown asembodied in a target throwing machine of the general type disclosed inmy prior U.S. Pat. No. 3,108,582, issued Oct. 29, 1963, to whichreference may be had for details not herein illustrated. In addition,the following description of the operation of the target throwing trapdisclosed in this patent isintended to supplement the understanding ofthe structure to which the present invention is in cooperativerelationship.

A box-shaped rotating platform 12 is provided which 1 serves as the basefrom which a target 10 is given an inivention an improvement in a targetthrowing trap which overcomes the problems previously mentioned. In therelease mechanism of the present invention, means are provided forrotating a release detent, which initially holds the target, about ahorizontal axis. As the release dentent is rotated, it moves parallel tothe flight path of the target and above the top of the target. Therelease detent moves away from the target faster than the initial speedof the target. Accuracy errors and'target breakage have decreasedbecause the friction between the target and the release detent issubstantially decreased due to the speed with which the detent moves outof the flight path of the target.

The release mechanism includes a horizontal shaft that is parallel tothe platform, a release detent located at the end of the horizontalshaft and a gear assembly tial rotation prior to entering flight. Thetargets are stacked above the center of rotation 11 of the platform, andmeans such as a concentric, movable disc, are provided to engage thetarget and lower it concentrically onto the rotating platform. A devicethen moves the target across the platform so that it is centered above apoint 13 eccentrically located. A release mechanism 14 and a guiderail15 hold the target until release.

In an exemplary embodiment of the improved release mechanism arrangedaccording to the present invention, as shown in FIG. 2, a target,represented generally by the reference numeral 10, is mounted on aboxshaped,'rotating platform 12 and held in position by the releasemechanism 14. The target 10 moves in a direction normal to the plane ofFIG. 1. A vertical shaft 16, which was referred to in the reference toU.S. Pat. No.

3,108,582, extends upwardly through a lower portion 18 of the rotatingplatform 12 and through a top surface of the rotating platform. An arm(shown only partially at 19 in FIG. 2 but disclosed in US. Pat. No.3,108,582) is mounted on the lower portion of the shaft 16 and is rockedin a plane at right angles to the axis of shaft 16 for imparting arotation in an arc of approxi- I mately 45 in response to a command torelease the target.

The release mechanism 14 includes a support structure 20, a horizontalshaft 22 that is parallel to the platform 12, a gear assembly 24, and atrigger detent 26. The trigger detent is preferably padded with aresilient material 29 (see FIG. 3), such as rubber, to cushion thecontact of the detent with the target 10. The support structure 20includes a pair of upwardly extending arms 28 and 30 having openings toreceive the parallel shaft 22. The support structure 20 also has anopening to receive the shaft 16. A series of bushings 17, 21 and 23 areprovided to permit the shaft 16 to be rotatively held in its position.

The release mechanism 14 is mounted on the rotating platform 12. A lowersupport base 32, located on the underside of the rotating platform 12,is rigidly secured to the rotating platform 12 by a fastener 34 that ispositioned in openings in both members. The support 20 is then securedto an upper base plate 36 by a fastener 40. The upper base plate 36 isthen secured to the lower support base 32 by a fastener. 38. Thefastener 38, as shown more clearly in reference to FIG. 3 is mounted ina slotted track to permit angular adjustment of the release machanismabout the axis of the vertical shaft 16.

The vertical shaft 16 has mounted on its upper end a gear 42 that isadapted to engage the teeth of a gear 44 mounted around the shaft 22.Preferably, the gear assembly 24 has a 2 to 1 transmission ratio,suchthat a 45 arc in the vertical shaft 16 induces a 90 arc in thehorizontal shaft 22. A pair of bushings 25 and 27 are located around theshaft 22 and within the openings in the structure 20. The outermost endof the shaft 22 has a pair of fasteners 46 and 48 that secure thetrigger detent 26 to the horizontal shaft 22. The trigger detent 26holds the target 10 stationary by contacting the circumference at arecessed rim 50 on the target 10.

The trigger detent 26 in FIG. 2 is shown after is has rotated 90,thereby releasing the target. The position of the detent 26 prior torotation is shown by the broken lines at 35.

In operation, the trigger detent 26 rotates from the vertical position,shown in FIG. 2 by the broken lines at 35 to the horizontal positionshown in FIG. 2 and FIG. 3. During this motion, there is no contact ofthe detent 26 with the target 10 at the recessed rim 50 due to the speedat which the shaft 22 rotates and due to the motion of the detent 26 inmoving outwardly and upwardly from the flight path. Thus, frictionbetween target 10 and trigger detent 26 is reduced to zero which in turnreduces flight path error and pre-flight target breakage.

Referring now to FIG. 3, the support base 36 is shown with a slottedtrack 52. The plate 36 may be adjusted by loosening the fastener 38 androtating the plate 36 about the shaft 16. FIG. 3 indicates the positionof the trigger detent 26 at the moment of release of the target whereinthe detent 26 rotates 90.

There is an optimum positioning of the target 10 that provides a vectorbalance at a particular point on the rotating platform to give optimumaccuracy of flight. A dotted line 56 indicates, as an example, thepositioning of the target where the release mechanism 14 is rotatedinwardly as shown by an arrow 58.

Referring now to FIG. 4, a modification of the structure of the releasemechanism 14 is shown. The horizontal shaft 22a is formed with a bend at60 to form an end portion 62 of the shaft 22a. The end portion 62 servesthe same purpose as the trigger detent 26 in FIG. 1 and FIG. 2. In FIG.3 the shaft 22a is shown at the time of release wherein the shaft 22ahas rotated 90". A replaceable rubber sleeve 64, secured to the endportion 62 by a washer 66 and fastener 68, cushions the contact betweenthe end portion 62 and the target 10.

The principal objectives of this invention may be achieved as long asthe surface of the detent, which engages the target in its position ofrest, moves away from the target, with a component of velocity in thedirection along which the target travels, which component is greaterthen the velocity at which the target moves out of its position of restunder the influence of the centrifugal forces acting upon it. Underthese conditions when the detent is moved so as to release the target,the target will move from its position of rest on the platform surfacewith no interference from the detent. Therefore it is to be understoodthat the detent 26 may be given other types of motion than thatheretofore illustrated. For example, the shaft 22 might be disposedbelow the target and rotated so as to rotate the detent 26 downwardlythrough an opening in the platform 12. Alternatively the shaft 22 mightbe disposed to one side of the target 10 with its axis verticallydisposed so as to move the detent 26 in a horizontal path away from thetarget. Likewise other means for moving the detent in the requiredmanner may be devised.

I claim:

1. A target throwing arm comprising:

a. a target b. a throwing arm having a free path surface of travel for atarget, said throwing arm being adapted to be continuously rotated andto support a target at a position on its surface eccentrically disposedwith respect to the axis of rotation of said throwing arm, whereby saidtarget is impelled to move along said free path along said surface ofthe under the influence of the centrifugal forces generated by therotation of said throwing arm;

0. detent means carried by said throwing arm and adapted to engage aforward edge of said target to restrain the target's movement along thefree path surface of the throwing arm said throwing arm having a meansconnected thereto for operating said detent means, said last mentionedmeans including a shaft; and

d. means connected to the shaft for moving said detent means away fromsaid target in response to rotation of said shaft so as to give thedetent means a horizontal component of velocity substantiallyparalleling said free path and of a greater value than the velocity atwhich said target is impelled to move along said free path of saidthrowing arm.

2. A target throwing trap as in claim 1 in which said detent is coveredwith a resilient pad on the target contacting surface.

3. A target throwing trap as in claim 1 in which said shaft is mountedon said platform with its axis disposed outside the path of motion ofsaid target, said detent being mounted on said shaft and projectingtherefrom into a position to contact said forward edge of said target inone position of said shaft, said shaft being adapted to rotate throughan arc, in response to release of said target, the rotation of saidshaft being sufficient to move said detent out of the path of saidtarget.

4. A target throwing trap as in claim 1 in which the axis of said shaftis disposed above said throwing arm and, whereby said shaft moves saiddetent upwardly in a plane perpendicular to the plane formed by the freepath surface.

5. A target throwing trap as in claim 4 further including a rotatablesecond shaft extending through said throwing arm which is operativelyconnected to said first named shaft to rotate said first named shaft inrespect to the target at release.

v Q j UNITED STATES PATENT OFFICE V V i 5 CERTIFICATE CORRECTION PatentNo. :1 8nn;775 Dated April 2 4 Inventor(s) George H. Darrell 7 hiscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:-

' column 4, line 48, in line 1 of claim 1, after ."surface of the"insert throwing arm ,Column- 4, line 65, in line 1 of claim' 2, cancel"trap" and substitute arm I Column 5, line 1, in line 1 of claim 3-,cancel "trap" and substitute arm Column 5, line 10, in line 1 of claim4-, cancel vColumn 5 line 10, "trap" should read arm Column 6, line 1,in line 1 of claim S, cancel "trap" and substitute arm Column 6, line 6,in line 1 of claim 6, cancel "trap" and substitute arm 7 Column 6, line11, in line 1 of claim 7, cancel "trap" and substitute arm I Signed andsealed this 29th day of October 1974.

(SEAL) Attest V M cCOY M. GIBSON JR. (2. MARSHALL DANN Att'estingOfficer I Commissioner of Patents FORM PO-JQSOHO-SS) x USCOMM-DC60376-P69 U.5. G OVERNMENT PRINTING OFFICE: I969 0-366-334

1. A target throwing arm comprising: a. a target b. a throwing armhaving a free path surface of travel for a target, said throwing armbeing adapted to be continuously rotated and to support a target at aposition on its surface eccentrically disposed with respect to the axisof rotation of said throwing arm, whereby said target is impelled tomove along said free path along said surface of the under the influenceof the centrifugal forces generated by the rotation of said throwingarm; c. detent means carried by said throwing arm and adapted to engagea forward edge of said target to restrain the target''s movement alongthe free path surface of the throwing arm said throwing arm having ameans connected thereto for operating said detent means, said lastmentioned means including a shaft; and d. means connected to the shaftfor moving said detent means away from said target in response torotation of said shaft so as to give the detent means a horizontalcomponent of velocity substantially paralleling said free path and of agreater value than the velocity at which said target is impelled to movealong said free path of said throwing arm.
 2. A target throwing trap asin claim 1 in which said detent is covered with a resilient pad on thetarget contacting surface.
 3. A target throwing trap as in claim 1 inwhich said shaft is mounted on said platform with its axis disposedoutside the path of motion of said target, said detent being mounted onsaid shaft and projecting therefrom into a position to contact saidforward edge of said target in one position of said shaft, said shaftbeing adapted to rotate through an arc, in response to release of saidtarget, the rotation of said shaft being sufficient to move said detentout of the path of said target.
 4. A target throwing trap as in claim 1in which the axis of said shaft is disposed above said throwing arm and,whereby said shaft moves said detent upwardly in a plane perpendicularto the plane formed by the free path surface.
 5. A target throwing trapas in claim 4 further including a rotatable second shaft extendingthrough said throwing arm which is operatively connected to said firstnamed shaft to rotate said first named shaft in response to rotation ofsaid second shaft.
 6. A target throwing trap as in claim 4 in which thedetent rotates through an arc of approximately 90*, the portion of thedetent contracting the rotating target moving upwardly and outwardlyaWay from the target during release.
 7. A target throwing trap as inclaim 1 including means for adjusting the position of the detent withrespect to the target at release.